A conventional arrangement is described in German Patent Application No. 1 95 28 62. In this publication, as the substrate a circuit board is indicated, which on its upper side is provided with an electronic circuit, which includes at least one power component that generates waste heat. Beneath the power component, the circuit board is provided with via holes, which divert the heat generated by the power component to the lower side of the circuit board. Between lower side of the circuit board and a control unit housing functioning as a heat sink, a thermally conductive filler is arranged. During operation, the heat produced by the power components is diverted via the via holes to the lower side of the circuit board and from there is delivered via the thermally conductive filler to the housing, which functions as a heat sink. In this context, it is disadvantageous that printed circuit traces that conduct potential on the lower side of the circuit board can come into contact with the heat sink during assembly of the circuit board in the control unit. A short-circuit that is caused in this way can damage or destroy the sensitive electronic components on the circuit board.
In addition, German Patent Application No. 1 97 23 409 describes an arrangement having a substrate and a heat sink. On the upper side of the circuit board, a power component is deposited on a large-surface printed circuit trace, which is connected by via holes to a large-surface printed circuit trace on the lower side of the circuit board. On the lower side of the circuit board, a metal layer is deposited under the large-surface printed circuit trace arranged there and over an insulation layer, which in turn is deposited through a solder stop mask onto a control unit housing part that is provided as a heat sink. In this arrangement, although an electrical contact between the printed circuit traces and a heat sink is prevented by the insulation layer, it is disadvantageous that the insulation layer and the further metal layer complicate the direct heat transfer to the heat sink, increase the space requirements of the arrangement, and also make manufacturing more expensive.